Saturday, April 07, 2012

Ni, Pd, Pt, and Ru Complexes of Phosphine-Borate Ligands

7/abril/2012

Paulina Levario

The species Cy2PHC6F4BF(C6F5)2 reacts with Pt(PPh3)4 to yield the new product cis-(PPh3)2PtH(Cy2PC6F4BF(C6F5)2) 1 via oxidative addition of the P–H bond of the phosphonium borate to Pt(0). The corresponding reaction with Pd(PPh3)4 affords the Pd analogue of 1, namely, cis-(PPh3)2PdH(Cy2PC6F4BF(C6F5)2) 3; while modification of the phosphonium borate gave the salt [(PPh3)3PtH][(tBu2PC6F4BF(C6F5)2)] 2. Alternatively initial deprotonation of the phosphonium borate gave [tBu3PH][Cy2PC6F4BF(C6F5)2] 4, [SIMesH][Cy2PC6F4BF(C6F5)2] 5which reacted with NiCl2(DME) yielding [BaseH]2[trans-Cl2Ni(Cy2PC6F4BF(C6F5)2)2] (Base =tBu3P 6, SIMes 7) or with PdCl2(PhCN)2 to give [BaseH]2[trans-Cl2Pd(Cy2PC6F4BF(C6F5)2)2] (Base = tBu3P 8, SIMes 9). While [C10H6N2(Me)4H][tBu2PC6F4BF(C6F5)2] 10 was also prepared. A third strategy for formation of a metal complex of anionic phosphine-borate derivatives was demonstrated in the reaction of (COD)PtMe2 with the neutral phosphine-borane Mes2PC6F4B(C6F5)2 affording (COD)PtMe(Mes2PC6F4BMe(C6F5)2) 11. Extension of this reactivity to tBu2PH(CH2)4OB(C6F5)3) was demonstrated in the reaction with Pt(PPh3)4 which yieldedcis-(PPh3)2PtH(tBu2P(CH2)4OB(C6F5)3) 12, while the reaction of [SIMesH][tBu2P(CH2)4OB(C6F5)3] 13 with NiCl2(DME) and PdCl2(PhCN)2 afforded the complexes [SIMesH]2[trans-Cl2Ni(tBu2PC4H8OB(C6F5)3)2] 14 and [SIMesH]2[trans-PdCl2(tBu2P(CH2)4OB(C6F5)3)2] 15, respectively, analogous to those prepared with 4 and 5. Finally, the reaction of 7 and 13with [(p-cymene)RuCl2]2 proceeds to give the new orange products [SIMesH][(p-cymene)RuCl2(Cy2PC6F4BF(C6F5)2)] 16 and [SIMesH][(p-cymene)RuCl2(tBu2P(CH2)4OB(C6F5)3)] 17, respectively. Crystal structures of 1, 6, 10, 11, 12, and 16 are reported.

For more information:

Ni, Pd, Pt, and Ru Complexes of Phosphine-Borate Ligands

Stephanie L. Granville, Gregory C. Welch, and Douglas W. Stephan

Inorganic ChemistryArticle ASAP

Department of Chemistry, University of Toronto, 80 St. George St. Toronto, Ontario, Canada M5S 3H6